From 0b922b7a829c06e3b0790c58cd9ca026de86096e Mon Sep 17 00:00:00 2001 From: David Ahern Date: Tue, 10 May 2016 11:19:51 -0700 Subject: [PATCH] net: original ingress device index in PKTINFO Applications such as OSPF and BFD need the original ingress device not the VRF device; the latter can be derived from the former. To that end add the skb_iif to inet_skb_parm and set it in ipv4 code after clearing the skb control buffer similar to IPv6. From there the pktinfo can just pull it from cb with the PKTINFO_SKB_CB cast. The previous patch moving the skb->dev change to L3 means nothing else is needed for IPv6; it just works. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- include/net/ip.h | 1 + net/ipv4/ip_input.c | 1 + net/ipv4/ip_sockglue.c | 7 ++++++- 3 files changed, 8 insertions(+), 1 deletion(-) diff --git a/include/net/ip.h b/include/net/ip.h index 247ac82e9cf2..37165fba3741 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -36,6 +36,7 @@ struct sock; struct inet_skb_parm { + int iif; struct ip_options opt; /* Compiled IP options */ unsigned char flags; diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index 37375eedeef9..4b351af3e67b 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -478,6 +478,7 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, /* Remove any debris in the socket control block */ memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); + IPCB(skb)->iif = skb->skb_iif; /* Must drop socket now because of tproxy. */ skb_orphan(skb); diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index bdb222c0c6a2..5805762d7fc7 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -1193,7 +1193,12 @@ void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb) ipv6_sk_rxinfo(sk); if (prepare && skb_rtable(skb)) { - pktinfo->ipi_ifindex = inet_iif(skb); + /* skb->cb is overloaded: prior to this point it is IP{6}CB + * which has interface index (iif) as the first member of the + * underlying inet{6}_skb_parm struct. This code then overlays + * PKTINFO_SKB_CB and in_pktinfo also has iif as the first + * element so the iif is picked up from the prior IPCB + */ pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb); } else { pktinfo->ipi_ifindex = 0; -- 2.20.1